The present invention relates to a device and a method for the quantified evaluation of surface characteristics.
The invention is described in respect to varnished surfaces in particular in respect to the surfaces of bodies of automobiles. However it is pointed out that the present invention can also be used with other surfaces.
In numerous technical products the condition of the visible surfaces is a crucial characteristic for the overall impression of the product.
Automobiles are usually provided with a high gloss varnishing whose gloss characteristic value is normally far higher than the gloss characteristic value of other surfaces, for instance, furniture surfaces and the like. The high gloss of the varnishing used and the relatively big surfaces require an exceptionally careful preparation of the surfaces to be varnished and a very careful application of the varnish. In order to identify quality defects of varnished automobile body surfaces devices are known from the state of the art which permit an objective characterization or evaluation of the surfaces by the evaluation of light radiated thereon. By means of these devices, for instance, unevenness in the varnish layers can be detected and evaluated quantitatively.
The varnishes typically used in the automobile industry not only have an outer varnish layer but basic varnish layers lying under said outer varnish layer. In order to produce qualitatively acceptable final layers it is necessary to also check the condition of the respective basic varnishes. In doing so, the problem appears that these basic varnishes relatively weakly reflect light radiated on them and hence an evaluation of this basic varnish is very elaborate.
Hence it is an objective of the present invention to create a device which also permits an evaluation of the basic varnishes.